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BULLETIN 15 8, UNITED STATES NATIONAL MUSEUM 



garded this as the most common form of Cyclops in temporary pools, 

 and one of them has given in the American Naturalist (vol. 15, 

 p. 736) an account of finding this copepod swarming in rain pools, 

 filled overnight, near Salem, Iowa. The fifth legs furnish the best 

 identification for this species. 



CYCLOPS BICUSPIDATUS Claus 



Figure 193 



Cyclops bicuspidaius Claus, Arch. Nat., Wiegmann, vol. 1, Jalirg. 28, p. 209, 



pi. 11. 1857. 

 Cyclops pulchellus Saks, Crustacea of Norway, vol. 6, p. 47, pi. 27, 1913. 



Occierrence. — Reported by Pearse from Nantucket Island in the 

 American Naturalist (vol. 40, p. 248) and by E. B. Forbes from a 

 pond in Woods Hole in the Bulletin of the Illinois State Labo- 

 ratory of Natural History (vol. 5, 

 p. 44). 



Distnhutlon. — Germany (Claus) 

 Europe, Asia, Norway (Sars) ; 

 England (Pratt) ; North America 

 (H e r r i c k) ; Massachusetts 

 (Forbes) ; Wisconsin lakes, Indiana 

 (Marsh) ; Great Lakes (E. B. 

 Forbes). 



Golo7\ — Body a light yellow, 

 more or less tinged with orange or 

 red; rarely a uniform whitish 

 gray; eye reddish. 



Female. — Body slender, meta- 

 some oblong, oval, width less than 

 half the length; urosome less than 

 half the length of the metasome; 

 genital segment considerably wid- 

 ened anteriorly ; the posterior mar- 

 gins of all the segments except the 

 last serrate; caudal rami varying 

 greatly, from two to eight times as long as wide, their inner margins 

 usually ciliated, outer seta near the center of the ramus. 



First antennae 17-segmented, reaching the posterior margin of the 

 cephalic segment; rami of first four pairs of legs 3-segmented, end 

 segments of exopods with 2, 3, 3, 3 spines. Fifth leg 2-segmented, 

 basal segment as wide as long with one seta; distal segment twice 

 as long as wide, the apical seta three times the length of the lateral 

 one. Semen receptacle the shape of a bowl with a flaring rim and 



Figure 193. — Cyclops Mcuspidatus: a, 

 Male, dorsal ; ft, male, fifth and 

 sixth legs ; c, female, fifth leg 



